Numerous commercial and industrial businesses use VOCs in day-to-day operations. Many of these VOCs are dangerous to human health and the environment if released to soil and groundwater. For example, the dry cleaner industry has historically used a variety of solvents in the cleaning process, including volatile organic solvents such as kerosene, Stoddard solvent, gasoline, propylene glycol ethers and carbon tetrachloride. More recently, the majority of dry cleaner operations use tetrachloroethene or perchloroethene (PCE) as a cleaning solvent. This VOC is a known cancer-causing agent in animals and may cause cancer in humans. Almost 95% of dry cleaner facilities use PCE in their cleaning processes.
When released and allowed to seep into the ground even small quantities of PCE can contaminate large quantities of soil and groundwater at levels dangerous to human health and the environment. Government prescribed cleanup levels for PCE are as low as 0.05 milligrams per kilogram in soil and 5 micrograms per liter in groundwater. A release of one gallon of PCE can contaminate 100 million gallons of groundwater to twice the prescribed cleanup level, and result in cleanup liability of hundreds of thousands and potentially millions of dollars.
Given the liabilities associated with contamination cleanup, the insurance industry has been reticent to insure real estate against environmental risks where dry cleaner operations are ongoing or have previously occupied space on the property. Property owners are unable to sell properties or can only sell at reduced prices because of the risk associated with owning properties previously occupied by dry cleaner operations. Other businesses that use, store or treat or recycle VOCs, such as metal plating and fabrication plants, are affected similarly.
Currently there is no practical system or method to periodically monitor, in an efficient and cost effective manner, the subsurface at business facilities where VOCs are used. Typically, subsurface investigations occur only when an audit, insurance review or property sale takes place, or when a large release is documented. These investigations generally involve installing soil borings and groundwater monitoring wells to determine if a release has affected the soil and/or groundwater. By the time an investigation is performed the damage is done and the problem could have been spread by groundwater flow to contaminate millions of gallons of groundwater and migrated beyond property boundaries. In addition, subsurface investigations involving soil borings and monitoring wells are expensive, with costs ranging to hundreds of thousands of dollars. Environmental professionals are required to design these investigations, manage boring and well installation, interpret data, and report results.
Thus, there is a need for an inexpensive system, method and apparatus to monitor facilities where VOCs are used to determine if a release has occurred. The monitoring will determine if problems already exist or will catch future releases in a timely manner to facilitate mitigation before the cost of cleanup escalates.